1. Technical Field
The present invention relates to a contact structure, a semiconductor device employing the same, and methods of manufacturing the same.
2. Discussion of the Related Art
Non-volatile memory devices can retain stored information even when not powered. Some examples of non-volatile memory devices include read-only and flash memory devices.
Research has been performed on memory devices with structures that have nonvolatile memory characteristics and increased integration density. This research has led to the development of a phase change memory device.
In a phase change memory device, a contact structure may be formed on a data storage pattern. However, when the data storage pattern has a recessed region in its upper surface, stable contact with the contact structure may not be realized. Accordingly, there is a need to improve the contact characteristics of a data storage pattern having a recessed region in its upper surface.